Passage and propagation of food (solids and liquids) through the gastrointestinal (GI) tract is facilitated by the process of peristalsis. Peristalsis involves a distinct pattern of smooth muscle contractions of the gastrointestinal tract that facilitate the propulsion of food distally through the esophagus, stomach and intestines.
In addition to the natural pacing from the body, distension and mucosal irritation of the GI tract stimulates afferent neurons. These sensory neurons synapse with two sets of motor neurons, which lead to two distinct effects. In one instance, a group of sensory neurons activate excitatory motor neurons proximal to the bolus of food. The excitatory motor neurons stimulate contraction of smooth muscle. In another instance, a different group of sensory neurons activate inhibitory motor neurons. The inhibitory motor neurons relax smooth muscle distal to the bolus. The coordinated excitatory and inhibitory motor neuron activity propels the bolus of food forward. This process is repeated in a sequential pattern as it is regulated by the natural pacemaker frequency of the GI tract. Localized distension of the GI tract is a natural consequence of the process of peristalsis as the bolus of food is propelled forward.
Common motility disorders of the gastrointestinal tract are gastroparesis and ileus. Gastroparesis is a disorder that affects motility of the stomach in the absence of mechanical obstruction. Causes of gastroparesis are not fully understood but can be associated with diabetes, surgeries, medications, and disruption of normal neuronal stimulation of the GI tract. Surgical procedures, especially those involving the abdomen and thorax, can result in significant dysregulation of normal gastrointestinal activity. Disruption of normal peristalsis can lead to delayed gastric emptying and at the extreme, ileus. When ileus develops after a surgical procedure, it is commonly known as post-operative ileus (POI). POI is a major contributor to postoperative discomfort, prolonged hospitalization and surgical complications.
While a number of attempts have been made at electrically stimulating the GI tract, they have been ineffective in consistently stimulating peristaltic activity. These methods primarily use electrical stimulation applied via temporary or permanent leads/implants and can range from being highly invasive to being less invasive. In one example, electrical stimulation of the GI tract is applied immediately after a procedure via surgery and thus is not well tolerated by patients with pre-existing motility disorders and those already recovering from surgeries
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.